Table 2 contains comparative statistics regarding preoperative risk factors.
The first technology assessment addressed preoperative testing in elective surgery.
Preoperative radiography demonstrated a left-sided heart and descending aorta.
Preoperative angiograms were unavailable for 5 patients, and postoperative films were unavailable for an additional 2 patients.
Repeated catheterization for preoperative evaluation at nine years of age showed essentially similar findings.
The rule ofclosure may be broken when there is no preoperative regurgitation and the edges of the adjacent leaflets are very thin.
Both reports (5;7) considered that the indications for preoperative investigation might have a large economic impact on health care.
In retrospect, however, the anatomy could be distinguished on preoperative echocardiograms.
